Apparatus for metered feeding of granular materials



G. OHO'LM 2,886,216

APPARATUS FOR METERED FEEDING OF GRANULAR MATERIALS May 12, 1959 FiledAug. 23, 1955 ammo Uflifid Sees ic v APPARATUS FOR METERED FEEDING OFGRANULAR MATERIALS Gustav onolm, Bromma, Sweden, assignor toAktiebolaget Svenska Flaktfabriken, Stockholm, Sweden Application August23,1955, Serial No.530,135

priority, application Sweden August 26, 1954 2 Claims. (Cl. 122-282) Thepresent invention refers to an apparatus for metered feeding of granularmaterials, said apparatus consisting of a winged wheel rotatable arounda horizontal shaft, the winged wheel being positioned in a cylindricalcasing, provided with inlet and outlet openings. A drawback ofpreviously known winged wheels of this type is that during the rotationof the wheel the material often is damaged, owing to the fact that theouter layer near casing is crushed. Particularly when feeding grain andthe like this causes a considerable decrease in quality. The object ofthe present invention is to eliminate this drawback and to operate thewheel with the sections or pockets not entirely filled.

The apparatus according to the invention is characterized in that theinlet opening is arranged in the upper quadrant at one side of thecylindrical surface of the casing-when rotating clockwise arranged inthe left quadrant and vice versain such way, that a line drawn from thecentre of the winged wheel through the upper edge of the inlet openingforms an angle with the horizontal plane smaller than the angle ofrepose of the material to be fed. The position of the upper edge of theopening may according to a suitable embodiment of the invention beadjustable by means of a movable damper blade. The outlet opening of theapparatus may suitably be positioned in the cylindrical surface of thecasing in a quadrant which is situated diametrically opposite to theinlet opening whereby more complete sealing is obtained between theinlet and outlet openings. For the purpose of equalizing the pressuredifierence, if any, the apparatus advantageously may be provided with apipe equalizing the pressure between two openings positioned on eachside of the outlet opening at such relative angular distance, that saidpipe connects the sector or pocket about to be filled with the sector orpocket about to be emptied.

The invention will now be described more in detail with reference to theaccompanying drawing. The figure shows a section of a suitableembodiment of an apparatus for metered feeding of granular materialaccording to the invention.

In the drawing 5 is a winged wheel rotatable around a horizontal shaft6. 4 indicates a cylindrical casing around the winged wheel 5. Thiscasing is provided with an inlet opening 1 and an outlet opening 10. Inthe illustrated embodiment it is intended to cause the winged Wheel torotate clockwise. as indicated by the arrow. According to the drawingthe inlet opening is placed in the left quadrant of the casing in such amanner that a line drawn from the centre of the Winged wheel through theupper edge line 16 of the opening forms an angle 15 with the horizontalplane, smaller than the angle of repose 12 of the material 14 to be fed.With reference to the drawing, it is noted that the difference betweenthe angle 15 and the angle 12 causes a triangular space to be left emptyin the pocket. As the wheel 5 rotates clockwise, the material in thepocket shifts so that the empty space appears at the top of the wingedwheel about the casing."

ing 13 will be at one atmosphere.

S'from the granular material and thereby prevents crushing of thematerialv between the wings and the cylindrical wall of the casing 4.Thus; this construction effectively prevents crushing of the material asit travels with'the According to a suitable embodiment theposition ofsaid edge line16 may be adjusted by means of, a movable damper blade 2,which by means of the locking device 3 can be adjusted inthe desiredposition.

Thus, by adjusting the damper blade 2, the upper edge of the inletopening may beadjusted to accommodate different angles of repose. Forexample, when the material has a smaller angle of repose, the blade 2may be adjusted to the dotted line position to insure that the pocket isnot completely filled as the wheel rotates past it.

8 indicates a pipe for the equalizing of pressure between two openings 7and 13 on each side of the outlet opening and connecting the sector 11,which in turn is to be filled, with the sector 9 in turn to be emptied.Thus, if there is a substantial pressure difference between the inletand outlet openings, the pipe 8 cuts the pressure difierence between thesectors and the openings by approximately one half. For example, if theinlet opening is at three atmospheres of pressure and the outlet openingis at one atmosphere of pressure, the filled sectors traveling from theinlet opening to the opening 7 (will be at three atmospheres. Likewise,the empty sectors or pockets traveling from the outlet opening to theopen- The pipe 8 will equalize the pressures in the sectors as they passthe openings 7 and 13 respectively to approximately two atmospheres sothat the pressure difference between the inlet opening and the sectorregistering with the inlet opening, is reduced to one atmospheredifference, and the pressure difference between the outlet and thefilled sector approaching the outlet opening is likewise reduced to oneatmosphere. This greatly reduces the ill elfect of a substantialpressure difference at the inlet and outlet opemngs.

Modifications of the present invention certainly are possible within thescope of the invention.

What I claim:

1. For metered feeding of granular material having a given angle ofrepose, apparatus comprising a casing having a cylindrical wall disposedabout ahorizontal axis and generally radial wall means in saidcylindrical 'wall defining inlet and outlet openings for the material,said inlet opening being contained within one upper quadrant of saidcasing defined between horizontal and vertical planes through its axis,a winged wheel having radial wings slidably engaging the cylindricalWall of said casing and mounted for rotation coaxially within saidcasing in a generally upward direction in said one upper quadrant, thewings of said winged wheel forming closed pockets by engaging saidcylindrical wall'continuously between said inlet and outlet openings topreclude substantial air-leakage between said inlet and outlet openings,said inlet opening being positioned so that a straight lineperpendicular to the axis of said casing passing through the uppermostpoint in said opening forms an angle with said horizontal plane smallerthan the said given angle of repose, whereby when eachpocket registerswith the inlet opening, the difierence in angles causes an open space atthe top of the pocket which frees the upper edge of the pocket from thegranular material and prevents crushing of the same between the wheeland the cylindrical wall as the wheel rotates, and an adjustable damperblade to adjust the uppermost point in said opening to accommodatematerials having different angles of repose.

H rai m a, May 12, .1959

2- F9! anged findin 9? $22 .41?! ma i having a given angle of repose,apparatus comprising a casing having a cylindrical wall disposed about ahorizontal axis and generally radial wall means in said casing dc;fininginlet and outlet openings, said inlet and outlet openings being atdifferent pressures and contained within opposite quadrants of saidcasing defined between horizontal and vertical planes through its axis,said inlet opening being positioned so that a straight lineperpendicular to the axis of said casing passing through the uppermostpoint in said opening forms an angle with said horizontal plane smallerthan the said given angle of repose, a winged wheel having generallyradial wings slidably engaging the cylindrical wall ofsaid casing andmounted for'rotation eta-axially within said cas ng, the wings of saidwinged wheel forminga plurality of closed pockets by engaging saideylindrical wall continuously between said inlet and outlet openings topreclude substantial air-leakage between said inlet and outlet openings,and conduit means opening into said casing to interconnect a filledpocket passing from said inlet toward said outlet opening with anemptied pocket passing from said outlet toward said inlet opening toequalize the pressure in said pockets.

RejerencesCited in the file of this patent UNITED STATES PATENTS1,061,400 Pelton May 13, 1913 1,370,764 Pokess Mar. v8, 1921 1,437,863Raymond Dec. 5, 19.22 1,723,211 Schmidt Aug. 6, 1929

